1. Institute of Solar Energy Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education) School of Physics and Astronomy Shanghai Jiao Tong University 800 Dong Chuan Road Shanghai 200240 China
2. School of Materials Sun Yat-sen University Guangzhou 510275 China
3. Institute for Solar Energy Systems Guangdong Provincial Key Laboratory of Photovoltaic Technology State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-sen University Guangzhou 510275 China
4. Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering Changzhou University Changzhou 213164 China